Degreaser control apparatus



June 1950 J. F. BLACK ET AL 2,510,859

DEGREASER CONTROL APPARATUS Filed March 15, 1946 5 Sheets-Sheet 1 INVENTORS JOHN F Bmcx Mrs .1. 6x510 June 1950 J. F. BLACK ETAL 2,510,859

DEGREASER CONTROL APPARATUS 3 Sheets-Sheet 2 Filed March 15. 1946 132 33 /\/\/\N\/\/\/\/ A/vvvvvvW INVENTORS JOHN E BLACK y JAMES I dxnzy TORNEXJ J. F. BLACK ET AL DEGREASER CONTROL APPARATUS June 6, 1950 3 Sheets-Sheet 3 Filed March 15, 1946 INVENTORS JbH/V]? BZACK BY Anus ,1 5x510 ATTORNEYS Patented June 6, 1950 DEGREASER CONTROL APPARATUS John F. Black, Rocky River, and James J. Skelly, Cleveland Heights, Ohio, assignors to Oirco Products Company, Cleveland, Ohio, a corporation of Ohio Application March 15, 1946, Serial No. 654,780

14 Claims.

This invention relates broadly to a degreasing apparatus and more specifically to mechanism for regulating the height of 'the solvent vapor generated in the degreasing tank.

tank illustrating the improved vapor level control unit in place therein;

Fig. 2 is an elevational view of the electric switch and operating mechanism therefor in- One of the objects of the invention is to proeluding diagrammatically the heater elements vide a solvent vaporizing unit having a plurality and electric connections therefor; of heating elements therein and a control mech- Fig. 3 is a diagrammatic view of the portion anism therefor which is designed to effect the of the control which constitutes the holding successive operation of the heaters in response circuit; to thermal changes at various elevations in the Fig. 4 is a similar view to that shown in Fig. 2, portion of the degreasing tank that constitutes the holding circuit relay being illustrated in its the solvent vapor chamber. actuated position;

Another object of the invention is to mount an Fig. 5 is a view similar to Fig. 4 showing the elongated thermostatic element in a degreaser electric switch mechanism with the thermostat in angular relation to the fluid level of the solvent bellows in a partially distended position; therein so that substantial areas of the element Fig. 6 is a View in perspective of a degreaser will be progressively enveloped by slight increases tank illustrating a modified form of the present in the elevation of the rising vapor from the invention in place therein; one side wall of the solvent during the heating operation. tank being removed in the interest of clarity;

Another object of the invention is to provide 0 and a mechanism to effect the successive operation 7 s an elevational view of the electric of a plurality of electric switches in response to switch and oper g mechanism therefor inthe action of a thermal control unit. cluding diagrammatically the heater elements,

Another object of the invention i to provide the distillation switch and thermostat and the a plurality of heating elements, a multi-contact electric connections therefor. switch therefor and a heat responsive device Referring first o t degreasing a being organized to effect the progressive opera- W ch y be of y 00I1Venti0na1f0rm,c0mtion of the heating elements under altitudinal prises genera ly a o t apor c a a thermal changes in the chamber within which sump in the base thereof for the reception of the heat responsive device is mounted. the fluid solvent and an electric heating unit A further object of the invention is to provide l2 i the ow r portion of the p- A11 inner a control mechanism for the height of the solvent side wall of the chamber H is p d W h a vapor in a degreaser, the mechanism being artube l3 disposed at an acute angle to the surface ranged to energize a portion of the total heating of the fluid solvent and pre y mounted to capacity consonant the amount of heating effect accommodate vertical adjustment of one d required. Thus a small drop in vapor level il thereof. The lower end of the tube I3 is sealed produce a small additional heating effect and a and the upper e d thereof s ou ted in fluid large drop in level will energize the full heating communication with an expansible bellows l4 capac1ty (Fig. 2). The tube and bellows are filled with Further objects of the invention reside in the a thermal expansive material of the character provision of a vapor level control device which cujstomarily used in heat responsive devices of is economic of manufacture, efficient of operathls type The bellows is Supported in a housing tion, durable of structure and susceptible of ingg g g gg 3:21: gg gfigg gsg gi ggg igalllation in degreaser tanks of various size or 46 rg f I: i z a 5105s on the ag end ereo w c s appe 0 receive a readed Qther (Meets and afiva'ntages more or 18:53 rod IT. The opposed end of the rod is supported anqfllery to the P 'e and the mimner by a spring l8 seated in a cup I9, secured to the which all the various ob ects are realized will housing 5 and a Second cup 20 amxed to the appear in the following description, which con- 50 rod n The rod is provided with a plurality f sidered in connection with the accompanying drawings, sets forth the preferred embodiment of the invention.

In the drawings:

Fig. 1 is a view in perspective of a degreaser switch fingers 2| actuating the moving contacts of switches 22 which are engaged respectively with contacts mounted on a plate 23 within the housing IS. The plate 23 is formed of an electrical insulating material and the rod I1 is likewise insulated from the metal housing by fiber discs 24 within the cup and cap l6.

As will be seen in Fig. 2, the electric heating unit embodies in part a pair of coils 25 coupled with a source of current through the lines 26 and 21, the line .26 being directly connected to one power line L-l while the other line 21 is connected to the second power line L--2 through the contacts of a holding circuit relay 28 and through a normally closed switch 29. The switch 29 constitutes the stop switch of one of the usual type starting switches, and. it is wired in series with the normally open switch 30 which constitute the starter switch of the combination. As shown in Fig. 2 the electrical circuit for the degreaser is in its "off or open condition and no current is flowing.

The holding circuit (Fig. 3) which serves to safeguard the operation of the degreaser should the vapor rise above a definite upper limit, comprises the relay'28 connected in series with switch fingers 2l-a and the switch 22--a in the multicontact switch assembly in the housing l5. The switch arm .2l--a is connected to line 2'! which, as pointed out above, is connected through the solenoid contacts and the stop switch 29 to the power line L2. One side of the solenoid coil is connected directly to the power line L- -.l, the opposedside being connected by line 3| to the switch contact 22-a.

' In operation, when the starter switch 36 is closed, the circuit of the solenoid 23 is completed from the power line Li through the coil, through a portion of the line 3!, the starter switch 30 and the stop switch 29 to the other power line L-2. The contacts of the relay 28 are thereby closed and the circuits through them are completed. As previously pointed out the solenoid coil is wired in series with the solenoid contacts and with the switch arm ,2la and the contact 22-11. Therefore, the solenoid is held in its actuated position until the circuit through the coil is broken, which can occur only by the opening of the stop switch or the movement of the switch arm 2la out of contact with the contact 22a. Likewise, the only method for closing the circuit through the coil of the solenoid 28 and heaters 25 is by closing the contacts of the starter switch 313. The heavy lines in Figs. 4 and 5 indicate the Wires in which a current is flowing, and the light lines indicate Wires in incomplete circuits. Fig. 4 represents the condition of the heaters and wiring immediately after closing the contacts of the starter switch 3.0.

With the holding circuit in its actuated position as illustrated in Fig. 4, current will flow from the power line L-I through. the heaters 2525 and 32, 33, 34 and 35, through the contacts 22a, 22b, 22c, 2212, 22c, the switch fingers 2lb, 2lc, Zld, 2le, the rod ll, the switch arm am, the line 21, the contacts of the relay 28, the stop switch 29 to the second power line lie-2.

The solvent vapor is appreciably heavier than air, and when confined by the side walls of the tank as provided herein, the vapor will rise in an even level stratum within the chamber l I. As the hot solvent vapor rises and progressively envelops the inclined tube i3, the thermal expansive material therein Will effect the distention of the bellows l4 and the lateral translation of the spring-held rod H. The inclination of the tube 13 is designed relative to the spaced relation of the switch fingers 2| and the expansive characteristic of the material within the tube so that incremental changes in height of the rising solvent vapor will effect progressive separation of the switch fingers 2i from the contacts 22 therefor. Hence, as will be seen in Figs. 1 and 5, when the portions of the tube up to lines B and C are submerged in the vapor, suihcient translation of the rod ll will have occurred to open the circuit through the switches Min-ZZZ) and 2lc-22c and thus break the circuit to the heating elements 34 and 35. It will readily be seen that further submersion of the tube will heat a greateramount of fluid therein and will cause further translation of the rod ll. Thus when the vapor level reaches the lines D and E the translation of the rod will break the circuits through the switch fingers Zld and Zle and. the contacts therefor 22d and 22e, which control the circuits through the heaters 33 and 32 respectively.

The thermal output capacity of the heating elements 2 3 425 is designed relative to the size of the degreaser tank and the heat losses therefrom to maintain the height of the solvent vapor at a point approximately midway between the surface of the fluid solvent and the line B in Fig. 1. Thus these particular heaters are in use throughout the operation of the degreaser, the further control of the height of the solvent vapor being governed by the selective control of the heaters 32, 33, 3t and 35.

During normal operation the switch finger Zia remains in contact with the contact 22a. The operation of the degreaser will be safeguarded by the action of the limiting switch arm 2 la, for in the event that the vapor in the chamber Ii reaches a predetermined maximum height line A in Fig. 1), the translation of the rod ll will be sufficient to separate the arm Zia from its contact 22a. This action breaks the holding circuit and the relay solenoid is de-energized restoring the circuit to the condition illustrated in Fig. 2. An additional safety thermostat may be installed in the tank adjacent the heating coils and Wired in series in the holding circuit similar to the thermostat 4? shown in Figs. 6 and 7. The function of the thermostat in either case is'to open the holding circuit and interrupt the current to all the heaters when the liquid solvent reaches a predetermined temperature.

It will be recognized that the sensitivity of the thermostatic element may be altered by adjusting the angle of the tube 13 in such a manner as to vary the length of the switch-controlling sec tions that are submerged in the vapor, or by rearranging the position of the switch fingers relative to their contacts and to each other. It will be further recognized that other operative characteristics of the thermostatically-controlled switches may be obtained by using a tube of tortuous form and arranging the connections therefor in such a manner as to eifect the time and/or requisite order of operation of the switches.

. In the modified embodiment of the invention illustrated in Figs. 6 and 7, the tank All is provided with the necessary equipment for purifying the spent or grease-laden solvent by distillation. A portion of the tank adjacent the upper edge is surrounded by a water jacket 4! designed to accommodate the circulation therethrough of cold water- The jacket 3! is provided with an inlet pipe 42 connected to a suitable source of cold water and outlet 43 open to the atmosphere and arranged to feed into adrain. The flow of .water into the jacket and the eonsequent cooling efiect of the wall of the tank encased thereby is controlled by a solenoid valve 44 installed in the water inlet and electrically connected to the modified vapor level control circuit illustrated in Fig. '7.

As will be seen in Fig. 6, the tank 4|! is provided with a trough or dam 45 secured to the inner surface of the side and end walls thereof subjacent the portion of the walls encased by the cooling water jacket 4!. Th distilling operation is effected by heating the spent solvent in the bottom of the tank at a rate adequate to raise the solvent vapor to the level of the water jacket 4|. The vapor in contact with the cold portion of the walls condenses and is collected in the dam whence it is drained through the solvent drain pipe 46.

A distillation thermostat 4'! is installed in the lower portion of the tank 40 and is arranged to interrupt the circuit to the heating coils l2 when the temperature of the solvent residue reaches a predetermined maximum.

The solvent vapor level control mechanism is similar to that of the preferred embodiment heretofore described and includes a thermal responsive element in the form of an elongated tube l3 secured to an inner wall of the tank 40 in acute angular relation with the horizontal. The upper end of tub i3 is preferably below the bottom of the dam 45 as in Fig. 6; however, it may be installed across the level of th dam either by forming the tube around the dam or interrupting the latter to accommodate the tube.

Referring now to Fig. 7 wherein is illustrated the vapor level control mechanism and the electric circuit therefor as modified to include the distillation control circuit, it will b noted that the vapor control mechanism is identical with the mechanism shown in Figs. 1 to 5. The box l5 houses the longitudinally adjustable rod ll supporting a plurality of switch arms 2|, the rod being actuated by the extensible bellows l4 in fluid communication with the tube l3.

In this embodiment the holding circuit through the switch Zia and 22a is altered by connecting the distillation thermostat 41 in line 3| in series relation with switch Ma and 22a. During distilling operation the vapor level is above the upper end of th tube [3 and the switch 21a and 22a is therefore held open. To prevent the breaking of the holding circuit, th switch 2| a and 22a is shunted through lines 48 and 49 and contacts h of a gang switch 50. The gang switch is designed to efiect the simultaneous making and breaking of a plurality of contacts 9, h, 7, k, l and m by the manual actuation of a switch rod 51. As shown, the switch arms are all connected to line 49 which in turn is connected to the switch arm 21a in the vapor control mechanism and thence to power line L--2 through the contacts of relay 28. Qne terminal of the solenoid coil of valve 44 is con; nected to line 26 and the other terminal is wired to contact g of gang switch 50. The four control heating coils 32, 33. 34 and 35 are connected to contacts :i, k, l and m respectively. It will readily be seen that actuation of the lever 5| to close the contacts of gang switch 5!) will energiz the heaters and the holding circuit regardless of the successive opening of the switches as biased by the bellows I4 in the vapor control mechanism. The simultaneous closure of the contacts 9 of switch 50, effects the opening of solenoid valve 44 and the flow of cold water through the water jacket 4|.

In operation for degreasing purposes the gang switch is opened leaving the vapor control circuit similar to that shown in Figs. 1 to 5, the only difference being the series installation of the distillation thermostat 4! in line SI of the holding circuit. Inasmuch as the thermostat 41 remains closed during degreasing operations with substantially pure solvent, the vapor level control mechanism and circuit therefor functions in a manner similar to that shown in Figs. 1 to 5.

When the solvent becomes so grease-laden as to preclude efficient degreasing it ma be purified by closing the distillation gang switch 50 which, as heretofore described, shunts the holding and heater circuits around the vapor level control mechanism and opens the coo-ling water valve 44. The solvent vapor, substantially free of grease, condenses on the cool portion of the walls, drains into the trough 45 and is collected through the solvent drain pipe 46. The heavy grease residue in the bottom of the tank 49 is then removed manually, the purified solvent together with sufficient new sol-vent is placed in the tank, and the degr aser is again ready for grease removal operations.

Although the foregoing description is necessarily of a detailed character, in order that the invention may be completely set forth, it is to be understood that the specific terminolog is not intended to be restrictive or confining, and that various rearrangements of parts and modifications of detail may be resorted to without departing from the scope or spirit of the invention as herein claimed.

The term lockout means as used in the claims defines a device which operates automatically from a first condition to a second but will not return from the second condition to the first without manual intervention.

What we claim is:

1. In a degreaser embodying a tank for a solvent, mechanism for control of the vaporization of the solvent comprising a pluralit of electric heating elements, a tube in the tank above the level of liquid solvent inclined downwardly so as to pass through the desired surface level of vaporized sol-vent, an extensible bellows in fluid communication with said tube, a thermal expansive material expanded in said tube and actuating said bellows, a rod coupled with said bellows, and electric switches actuated by said rod connected respectively to said heating elements, the switches being arranged for serial operation by movement of th rod.

2. In a degreaser embodying a tank for a solvent, mechanism for vaporizing the solvent and. controlling the solvent vapor level in the tank, comprising a plurality of electric heaters mounted 3. A degreaser comprising a tank for a sol vent, a plurality of electric heaters therein, an

elongated tube in said tank adapted to be progressively influenced by rising solvent vapor, an extensible bellows connected to said tube, a ther- -mal expansive material in said tube and bellows,

a multi-conta-ct switch actuated by said bellows, switch elements in said multi-contact switch arranged for sequential operation, electric connections between certain of the switch elements and the electric heaters, and thermostatically conasr sse trolled lockout switch means to interrupt th circuit to all of the heaters.

4. Ina degreaser embodying a tank for a solvent, mechanism for the control of the vaporization thereof comprising a plurality of parallelconnected electric heaters, an energizing switch for each heater, a tube in said tank above the level of liquid solvent arranged with one end thereof comprising a plurality of heaters, electric switches therefor, an elongated thermostatic element in the tank disposed above the level of liquid solvent and inclined towards the base thereof, and means actuated by said thermostatic element to efi'ect the sequential operation of said switches.

6. In a degreaser embodying a tank for a solvent and a plurality of electric heating elements,

mechanism for the control of said heater-s comprising a tube in the tank above the solvent level, an extensibl bellows in fluid communication with said tube, a thermal expansive fluid in said tube and bellows, a multi-contact switch actuated by said bellows, contacts in said switch electrically connected to the heating elements, a holding circuit arranged to control the flow of current to all of the heaters, and thermal responsiv means to interrupt said holding circuit.

7. A heater for vaporizing a solvent in a degreaser tank comprising a plurality of electric heating elements, a switch for the control of each of said elements, an elongated bulb in the tank above th liquid solvent level inclined to the vertical, a thermal expansive material in said bulb and means for actuating said switches successively by the expansion of said material.

8. A degreasing apparatus comprising a tank for a solvent, a plurality of electric heating ele- 'ments therein, electric switches for operating said elements, a thermostatic element for actuating said switches, means controlled. by said thermostat for operating certain of the switches suc 'cessively, and means for breaking and holding open the circuit to all of the switches simultaneously actuated by th thermostat upon increase in temperature of the thermostat above that required to open the said certain switches.

9. A degreaser comprising a tank for a solvent, i

a plurality of parallel-connected electric heatin elements therein, a multi-contact switch therefor,

each contact being coupled for the operative con- 'trol of a separate heating element, a thermostatic element for actuating said multi-contact switch,

and means actuated by said switch for breaking and holding open the circuit to all of said heating elements when certain of said contacts are broken. I

10. A degreaser comprising a tank for a solvent, a plurality of electric heaters therein, an elongated tube in said tank inclined to the vertical axis thereof and located above the liquid solvent level, an extensiblebellows connected to said tube, a thermal expansive material in said tube and bellows, a multi-contact switch connected to said bellows for successive operation of switch elements, electric connections between the switch elements and the heaters, the electrical connections for one of the switch elements being arranged to break the electric circuit to all of the heaters upon maximum actuation of the bellows.

11. A degreaser comprising a tank adapted to contain a solvent in liquid form in the lower part thereof, a heater for vaporizing the solvent, a temperature-responsive device in the tank in the region of the desired upper boundary of the vaporized solvent and extended in altitude so as to be progressively more strongly afiected by the vapor as the level thereof rises, and mean for progressively decreasing the energy of the heater as the vapor level rises controlled by the said device.

12. A degreaser comprising a tank adapted to contain a solvent in liquid form in the lower part thereof, a plurality of heaters for vaporizing the solvent, a temperature-responsive device in the tank in the region of the desired upper boundary of the vaporized solvent and extended in altitude so as to be progressively more strongly affected by the vapor as the level thereof rises, and means controlled by the said device for progressively deenergizing heaters as the vapor level rises on the device and progressively energizing heaters as the vapor level declines on the device.

13. A degreaser comprising a tank adapted to contain a solvent in liquid form in the lower part thereof, a heater for vaporizing the solvent, a temperature-responsive device in the tank in the region of the desired upper boundary of the vaporized solvent and extended in altitud so as to be progressively more strongly affected by the vapor as the level thereof rises, means for varying the energy of the heater controlled by the said device; and lockout means for deenergizing the heater actuated by the said device upon the occurrence of a predetermined vapor level.

14. 'A degreaser comprising a tank adapted to contain a solvent in liquid form in the lower part thereof, a heater for vaporizing the solvent, a temperature-responsiv device comprising an elongated sensitive element in the tank in the region of the desired upper boundary of the vaporized solvent and extended in altitude so as to be progressively more strongly affected by the vapor as the level thereof rises, and means for varying the energy of the heater controlled by the said device, the element being disposed at an acute angle to the horizontal so as to be more sensitive to vapor level.

JOHN F. BLACK. JAMES J. SKELLY.

REFERENCES CITED The following references are of record in the file of this patent:

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